Discovery of Anatotitan

The holotype, or specimen on which the genus is based, was a complete skull and most of a skeleton collected in 1882 by Dr. J. L. Wortman and R. S. Hill for famous American paleontologist Edward Drinker Cope. A second mostly complete skeleton (AMNH 5886) was found in 1904 in Hell Creek Formation rocks at Crooked Creek in central Montana by Oscar Hunter, a rancher. Potential second species A. longiceps was first added to Anatotitan by George Olshevsky in 1991. Mr. Olshevsky runs a Dinosaur Genera List here.